The Ruminant: Audio Candy for Farmers, Gardeners and Food Lovers - What our Ancestors Ate and Why it Matters Today

Episode Date: April 9, 2016

Today's guest: Stephen Le, author of 100 Million Years of Food. Stephen is an anthropologist who argues that if we want to understand the role of diet in influencing our health, we need to ease off of our obsession with nutrutional science and focus more on the role that evolution has played in defining the relationship between what we eat and how we feel.  Canadian listeners: the Canadian publisher will give away one copy of this book. Details within!

This is the Ruminant Podcast. I'm Jordan Marr. The Ruminant Podcast and blog wonders what good farming looks like and aims to help farmers and gardeners share insights with each other. At theruminant.ca, you'll find show notes for each episode of the podcast as well as the odd essay, book review, and photo-based blog post. You can email me, editor at theruminant.ca, I'm at ruminantblog on Twitter, or search The Ruminant on Facebook. Okay, on with the show.

Hey everybody, it's Jordan. So, last week we had an episode that once again focused on the practical aspects of farming and gardening, featuring a few short segments, which means that this week we are back to a longer form conversation and we broaden out our viewpoint to focus on kind of broader topics in food and agriculture. And I'm really excited to tell you that this week features a conversation with Stephen Lay, the author of 100 Million Years of Food. Stephen is an anthropologist and in his book he argues that we are focusing way too much on nutrition and nutrition science, and not enough on our ancestry and evolution when

it comes to figuring out the link between our diets and our health. It is a provocative book, to say the least, folks. It's just kind of full of paradoxes. For example, Stephen manages to make the argument that when a hardcore vegetarian and a hardcore paleo diet advocate start bickering over, you know, whose diet is better for our health, well, he argues that they're both right. He also spends some time arguing that exercise is not unequivocally good for us. And that guess what? We actually aren't consuming all that many more calories now than our ancestors did. And here's something that will

be of interest to all the veggie growers out there. Stephen, well, he kind of thinks that plants kind of suck, or at least they're not nearly as awesome for our diets as a lot of people like to believe. So we're going to get to that in just a minute. I also want to say that I heard from Robert, the owner of Mid-Atlantic Farm Sensors, who was featured on the show last week. Farm Sensors, who was featured on the show last week. And he said he's already had some really interesting submissions regarding his offer to offer a really steep discount to one listener of one of his Farm Sensor setups. So if you're wondering what that's about, you can check out last week's episode and we'll announce the winner, I guess, on an upcoming episode. I'm not sure exactly when. Anyway, it's time to get to my conversation with Stephen Lay. Two notes that I want to make about the conversation.

Stephen was in Vietnam on a cell phone when I interviewed him. So his feed isn't wonderful. It's all right. And it's, I guess, dang good for the fact that he was in Vietnam on a cell phone. But I apologize. It's not up to the usual audio standard. Second, if you're a Canadian listener and you would like to compete

for a free copy of 100 Million Years of Food, here's what you can do. Go and share the Facebook post at the Ruminants Facebook page. Go and find that page and then find the post for this episode and share it on your own timeline. Or go and find the tweet associated with this episode, which you can find if you search for at ruminant blog on Twitter and retweet it. Or send me an email and tell me what you think of the show doesn't have to be positive feedback. I would

just love to know what you think. And I will compile a list of all the people who participated in the contest. And I will have the Canadian publisher of 100 Million Years of Food, which is the publisher that helped line up the interview. I will have them send a free copy of the book to one listener. And to my American listeners, I'm really sorry. I was dealing exclusively with the Canadian publisher for this book. And so they American listeners, I'm really sorry. I was dealing exclusively with the Canadian publisher for this book. And so they're only going to be able to send the book somewhere in Canada. And if that makes you steamed, I want you to know that every Sunday morning, when I go to dig.com and like all of the best of last night's SNL clips have been shared there,

I can't watch them because what does it say? The uploader has not made them available in my country. So it goes both ways, I guess is what I'm saying. And yeah, I'll try and have something that includes you, some kind of contest very soon. Anyway, here's my conversation with Stephen Lay. I hope you enjoy it. And I'll talk to you briefly at the end.

Stephen Lay, thanks a lot for joining me on the Ruminant Podcast. Thank hope you enjoy it. And I'll talk to you briefly at the end. Stephen Lay, thanks a lot for joining me on the ruminant podcast. Thank you for having me. Stephen, you've written a book called 100 million years of food, what our ancestors ate and why it matters today. And it's all about the relationship essentially between our diets and our health. And in terms of that relationship, you argue you argue that we are, are too focused on reducing food to its nutrient components and not focused enough on the role of genetics and evolution in determining that relationship. And I guess, first of all, I'm wondering if I have that about right. Um, and also if you could explain, uh, what, what inspired you to write this book? Okay. Um regard to the first question about the over-focus on nutrients, there is an understandable tendency to think about food as a kind of medicine.

And we have this saying of you are what you eat. And so I think there's a lot of emphasis these days on trying to fine-tune our foods to optimize our health. And that makes sense. But it can also go to an extreme. And people get overly anxious about what they're eating. They try to get a lot of nutritional advice. They're tuned into what's the latest news on nutrition. And then they go to extremes, unfortunately, trying to eliminate or focus on different kinds of nutrients or superfoods in order to avoid chronic diseases. And so I think this has been an unfortunate trend. And we can talk a lot more about that if you want. And the second question about why

I decided to write this book, there were two main reasons. The first reason was that my mother passed away from breast cancer in 2010. And she was 66 at that time. And my mother's mother, my grandmother, passed away at the age of 92. And so there's almost a 30-year gap between my mother passing away and my grandmother at the age that my grandmother passed away. And so I wanted to understand what were the factors that were behind this huge difference. And it was also also I needed to get this information so that I could pass on

some sort of message to my relatives and to my friends and also to help myself avoid cancer in the future. And that was one reason. Then there was another reason which was that my best friend went on a paleo diet.

And since I just finished studying biological anthropology, studied human evolution at UCLA, I decided to do more research into this to find out about the long-term consequences of eating a lot of meats. Well, Stephen, that personal motivation that you describe for wanting to pursue this topic, it really comes through in the book, I just want to say. It's a really interesting book in the sense that you describe for wanting to pursue this topic. It really comes through in the book, I just want to say. You know, it's a really interesting book in the sense that

you're fairly rigorous in your coverage of the science, but it also reads a little bit like a personal journey or even a sort of a memoir of sorts. And yeah, I think you achieve a really nice balance there. But back to the science. In your book, you write that, you write that up to a point, and you were writing about kind of the early 20th century, science made some very important discoveries about certain nutritional deficiencies and how those deficiencies contribute to conditions such as rickets or beriberi. conditions, such as rickets or, or beriberi. But, but, you know, since then, science has made, in your words, a disappointingly scant progress in understanding the relationship between diet and health. You argue in your book that you you need to account for for for the variability of

ancestral diets. It's not like all of us have evolved essentially in the same way. Is that right? People who evolved in different parts of the world, when their diets were sufficiently different, then they developed genetic differences in processes in those foods. And, for example, the Maasai in East Africa, who have traditionally eaten a diet consisting of milk, blood, and cattle meat, especially for the warriors in this group.

There was a lot of cholesterol, a really high level of cholesterol in this kind of diet. And it seems that they have evolved a specific adaptation to an extremely high level of cholesterol in their diet. Another example is the Inuit in northern Canada and Alaska. They had a diet that was historically very low in sugars and in calcium. And so when Inuits are exposed to high levels of sugar and high levels of calcium, they develop health problems, dangerous levels, high levels of calcium in their blood.

So the specific ancestry of people matters, and particularly for people who can trace their ancestry to a specific region in the world. That being said, a lot of Americans don't know where their ancestors come from. They have this sort of mixed genetic background, and so the differences start to matter less in those cases. But for those people who know where they come from, then they can fine-t tune their diets according to the, uh, what their ancestors ate. Right,

right. Okay. And so that, that actually led me to wonder, uh, Steven, you know, an interest,

I really, I really love the way you structured your book. Um, you know, the, the, the, most of the chapters kind of take us sequentially through evolution going back

to before we were humans and, and, and, and the different foods that we evolved or that we, that we tended to eat. And then as we evolved, our diets changed, you know, you, you go all the way back and to a time when our, our distant, distant, distant ancestor species were, were, were eating insects and then kind of take us all the way through to the, to the present day. But it had me wondering, how long does evolution take for a given change, in this case, a change in our physiology that would allow us to properly digest a new food? Yeah, that's a great question. So the old view on this question was that it would take on the order of something like 50,000, 100,000 years

to develop a genetic adaptation to something like a new kind of food item. But just in the last 10 or 20 years, this view has changed dramatically. And now it's realized that in the last 10,000 years, which is a pretty short amount of time in evolutionary perspective, there's been a lot of genetic changes in humans due to rapid introductions of new foods. And so the most famous example is with dairy. Dairying was introduced around 9,000 years ago in northern Europe and also in East Africa and northern India.

And so in those places, people developed the ability to digest lactose, the sugar in milk. And so that was just on the order of about 9,000 years, which is a pretty short amount of time. That's only about 300 generations. So adaptations can occur quite rapidly. So, Stephen, 300 generations, or say 10,000 years, even if recent science is showing that adaptations can happen that quickly, it still poses a problem for modern humans who happen to be very, very obsessed with trying to optimize their diet for maximum health.

Just in the sense that that's still way, way, way too slow for an adaptation to take place, given how quickly our lifestyles have changed in comparison, say in the last 100 years or 200 years. It just seems like that's a huge barrier to actually being able to, you know, make our lifestyles and our diets work together for optimal health. Yes, that's right. So there's this term in evolutionary science, they call it the abyss equilibrium. And that means when there's a rapid change

in the environment of an organism. And usually in that case, the animal's health suffers. So just as you say, in the last couple of hundred years, there have been huge changes in food and lifestyles, and this has been blamed for a lot of these new diseases of civilization, as they call them. So yes, this is a concern. Stephen, a really interesting point that you make in your book that isn't, I think, otherwise

very obvious is that we need to understand that when we talk about our health and how our diet contributes to it, that often there is a trade-off between our short-term health and our long-term health, and that certain diets will maximize short-term health, whereas other things we could be eating are better for our longevity. And so I thought we could talk about that using the consumption of meat as an example. Could you take me through that? Sure. There has been a lot of research in the past couple of decades on caloric restriction.

And so the idea here was that people have noted from the 1930s that eating less calories seemed to prolong the lifespan of mice, lab mice. And when they extended these kinds of experiments to fruit flies and other organisms, they found that there was a general tendency for animals to live longer when they ate less. And so this sparked a lot of interest in humans. And we started to wonder if reducing calories would also extend lifespan in humans. And after decades of research, it now turns out that what really extends the lifespan of organisms

is not so much reducing calories, but reducing protein intake. And so across a lot of these animals that have been studied in labs, decreasing the amount of protein tends to increase the lifespan of the organism. And for biologists, this makes sense, because in terms of biology, there's basically two strategies for an organism. The organism can either have a very successful but short life, or a life that's less successful but longer.

By living longer, the organism would have a second chance to reproduce. So waiting for another day to reproduce. So there's these two basic kind of strategies. And it looks like eating a lot of calories, and in particular eating a lot of protein, can make an animal strong and able to reproduce in the short term. But from a biological point of view, that's fine. That's like some clothing that's very cheap, but would make the person attractive in the

short term. In the long term, it turns out that, again, eating a lot of protein probably makes an organism die sooner. And so if you look at it from the perspective of an athlete, an athlete needs to perform optimally in the early years. But the consequence of that is that the athlete has problems in later years. And if you think of a sumo wrestler, they eat huge amounts of protein and a lot of food in general, and they're extremely strong and formidable on a wrestling mat.

But then once they retire, then they start to have problems with diabetes and gout from the calories and all the meat that they've been eating over their career. So that's the kind of trade-off that we're looking at. Well, I just, I find that, I find that so fascinating, Stephen, because, you know, as I'm like many other people, I think and have thought a lot about my diet and my health.

And what's so funny is that, you know, I've never thought about it in those terms, I guess, frankly, because I didn't really know about it until I read your book. But what's, what's so interesting is that, that I think many of us, including myself, that we want both things, right? I want to have chiseled abs and a great body because I want to be attractive to people around me. Um, and I just want to feel like super charged and super healthy. But I also, when I, in terms of what I'm eating, I'm also thinking about wanting to live a long time. But they just, you know, you make a pretty strong argument

that they're not necessarily very compatible. That's right. You can, okay, so you can take this view to an extreme. And some people are going to opt for the really short-term, and some people would opt for the extreme long-term. And I think most of us will choose something in between. We'll want to—we'll have to—we want both. We want the health, and we want the long life. And so there's going to be a compromise between that. So a person who's going to choose that kind of compromise between long health and short-term health, they're not going to live as long as somebody who

focuses on reducing all of their protein. But that's okay. I mean, most people are fine living up until they're 70 or 80. They may not make it to 100, but I think that for most people, that's fine. When you look at the people who have lived the longest in the world, look at the people who have lived the longest in the world in these, what Ben Beeman calls the blue zones. In these cases, these people had really, really tough lives in their early years. They went through World War II. They went through near starvation and a lot of hardship, and they had to walk around all day under the sun. And life was not pretty, not pleasant for these people. But as a consequence of going through that extreme caloric and protein deprivation, later on in life, they had access to a lot of better medical care and war ended and they had better

food and in particular more meat. And so actually there's this strange effect of meat where if people eat meat in their early years, they can increase the risk of dying earlier from cancer. But if older people eat less meat, then they're actually at a higher risk of dying. So there's new research to suggest that meat has this double-edged effect where it matters in which life stage you're looking at. So people who are older actually need to eat more meat because they can become more frail. And so, yeah, there's this paradoxical effect of need. And it kind of makes sense when you look at it from the point of view of evolution and the life course of an individual. So I think it's something that we need to keep in mind.

Well, yeah, and then there's a similar paradox in the sense that you can, I mean, if you're right about what you're arguing about, you know, you can have, you can have a guy on a paleo diet arguing with a guy on a mostly plant and grain, you know, plant-based diet, arguing that their diet is better for optimum health. And it turns out in one sense, they're, they're both correct. That's right. Yeah, we have to be careful about how we define how.

That's right. Okay, so moving on, Stephen, I also, another part of your book that I found quite interesting was, you know, there's a very, very dominant belief that it's our, it's that one of the greatest contributors to obesity and other problems, modern problems of diet, particularly in Western countries, is that we eat way too many calories and that we expend a lot less energy than our ancestors. But in your book, you argue that if you analyze the science, this doesn't seem to be the case. Can you talk about that?

Yeah. One of the greatest puzzles in public health is the problem of obesity. And the old view of looking at obesity was that this is simply a problem of calories. It was a problem of input and output. If you have too much input and not enough output, then there will be an excess of calories, and those excess calories will be translated into excessive fat tissue. And this was believed to be the problem behind obesity. But it never made sense in terms of practical measures.

It was never possible, it had never been possible for doctors to advise patients to simply decrease their fluid intake and increase their physical activity levels. People end up gaining weight in the long run. around with the body like this, you actually...the body responds to the decrease in calories by reducing metabolism. So it looks like we have this...our bodies have this innate desire to maintain a constant weight. Our bodies don't like to lose weight and it also turns out that when people lose a lot of weight, they tend to die sooner. So this is kind of worrisome because doctors have been advising us to lose weight for a long time and it looks like it's neither feasible nor practical for health.

It's actually dangerous to do. And then there's other evidence too that suggests that today we're eating more or less the same amount of calories that our ancestors did and we're doing more or less the same amount of physical activity levels as our ancestors did when we adjust for metabolism. And yet we have this problem of obesity that our ancestors never faced. And yet we have this problem of obesity that our ancestors never faced. So this is a paradox. And this is the old line of research that's kind of frustrating in terms of the results. But now the emphasis has started to shift towards hormones.

And people are trying to understand what kind of hormones are affecting appetite and obesity. And one thing that we do know now is that walking does reduce obesity. And in the book, I give the example of the Amish. The Amish, in some places north of America, they don't use vehicles. They don't drive around a lot. So when people walk a lot of distance in a day, for example, Amish men in Ontario could walk 18,000 steps a day, which is roughly 18 kilometers in a day, or about 14 miles. Then when they walk so much,

they have zero obesity in their communities. then when they walk so much, they have zero obesity in their communities. And so it's not just the calories that are expended. It's something about the kind of activity that we do. And our bodies are really well adapted to walking and to constant, moderate physical activity. And so when we adopt our ancestral lifestyle, then obesity disappears. So I think that's an important lesson. Definitely. But it's, it's funny because you're, you're,

you're saying that separately from this idea that, that we, you know, we need to exercise more, right? Like it's not just any exercise. It's this idea that like, you know, that, that, that intense exercise, intensive exercise isn't necessarily going to achieve the same effect as just regular, you know, ideally daily walking. That's right. One of the problems of vigorous physical exercise, let's say a person goes to the gym for an hour a day during the week. Then after they do that intensive workout, what do they do? They go back home and they eat ravenously.

And because there are so many calories that are packed, our bodies are so good at extracting calories from food, it's almost impossible to avoid gaining weight back after you go to the gym. And so people end up in this really frustrating cycle where they work out and then they're so hungry that they binge and then they have to work out again and they binge. And so that has proven to be a consistent, a feasible strategy and frustrating for a lot of people. So, yeah, the physical exercise, I think, was a fad.

It started in the 1960s and is starting to reverse now. People are starting to realize that we simply need to find more time to do more moderate physical activity. We're not designed to do intensive physical activity. Can you also talk about the potential relationship between obesity and perhaps the fact that on average we're more bored than ever? our calories are consumed by our brains. Our ancestors used their brains a lot. They had to think constantly about how to survive.

And so they had a couple of challenges. They had the challenge of finding food to eat during the day. So they had to be really creative, have a great memory of all the different plants in a region that were edible and those that were poisonous. They had to figure out how to hunt animals that were really difficult to catch. And they also had to worry about social challenges like not getting killed by a neighboring tribe. And then on top of that, they had to find a mate and figure out how to court somebody. And once they got a mate, they had to figure out how to make sure that their mate wasn't sleeping with somebody else.

So there's this really high intensity drama that our ancestors lived in. And now when you fast forward to the present, we're living in this... We're no longer in a real folk opera. Now we're just living in this very bland, kind of monotonous life compared to what our ancestors faced. Very few people now in industrial societies face the danger of dying from making poor food choices or getting killed by a neighboring tribe. And so we watch TV instead to try to get some of that intensity back into our lives

but really we're using our brains a lot less and so as a consequence we're consuming less calories in terms of our brains and so that could be a potential link in terms of obesity, that the excess calories

that we now have from lack of using the brain may translate into greater levels of body mass. Hey, folks. Jordan jumping in real quick here with a request. I just want to remind you of a couple ways that you can help the show. Here's the thing. iTunes is still very dominant in how podcasts are discovered, not just for those who are using iTunes, but it turns out that a lot of other podcasting apps use the iTunes search

engine in their apps, which means that I could really use some reviews on iTunes. If any of you are using iTunes and can access your account in the iTunes store, if you could go find my podcast, and can access your account in the iTunes store. If you could go find my podcast, the ruminant podcast and, uh, give it a review, uh, it would,

it would really help other people find the podcast. So that would be something really cool you could do. And of course, uh, I would love it if, if in general, people could be retweeting each episode tweet or going and sharing posts, uh,

from the ruminant page on Facebook, uh, featuring posts featuring different episodes. That's all very, very helpful. Thanks very much. And here's the rest of my conversation with Stephen Lay. So Stephen, I want to move on and, you know, of, of most of the chapters in your book, as I said before, they focus on a food group and how, what, you know, how, what, what, what relationship we had to that food group in different stages of our evolution. how, what, you know, how, what, what, what relationship we had to that food group

in different stages of our evolution. Um, and, and so you go through, you have a chapter on insects and a chapter on fruit and a chapter on meat. Uh, but, but the only one I really want to talk about in this conversation is your chapter on plants. Um, and that's because you come down particularly hard on plants in your book. And I want to acknowledge right now my bias. I grow organic vegetables for my main living. But I thought that was pretty interesting. And I'm wondering if you came down so hard on them because you actually think plants are really terrible and you try and avoid them as much as possible in your diet? Or was this more of a reaction to the reverence that some people accord plants in thinking about optimum health?

Yeah, it's the latter. I think the objection that I have is the overemphasis, The objection that I have is the overemphasis, the adoration that we foster upon plants. Really, they're not superfoods. I eat a lot of plant foods myself. Most of my diet consists of plant foods. Plant foods are the main constituent of most traditional diets. From that point of view, we need to eat plant foods are the main constituent of most traditional diets. So from that point of view, we need to eat plant foods.

We have been eating plant foods for a long time. There's nothing wrong with eating a lot of plant foods in the way that traditional societies ate them. The objection that I have is when we take those plant foods and then we look at them as being kind of superfoods, and if you think about it, if you take a bunch of cardboard and cut it up and then you empty the contents of your medicine cabinet on that heap of cardboard,

and then you eat that, that's basically how we view salads today. We're eating a lot of food that's highly indigestible, and we're hoping for all the nutritional benefits. And of course, yeah, okay, if you eat a lot of medicine, you're going to get some sort of nutritional benefits. But I think that's the wrong way of thinking about vegetable and plant foods. They're a necessary component of a healthy diet or a traditional

diet. But the research has never really supported the amazing health benefits of a plant. It's easy to find in any particular plant, it's easy to locate a couple of nutrients that will have a positive effect. But really the question should be the effect of the plant on the overall health. And when you look at the big perspective, most studies don't show that plants eating a lot of plant food increases lifespan. On the other hand, we know that eating less meat does increase lifespan. So eating more plant food makes sense, but I don't think we should give them too much hype.

But that's where I got a little confused because it seems like there's a contradiction. You started off, just a minute ago, you said that most traditional diets are based on plants, and yet you say that there's really no established link between greater longevity or greater health and consumption of plants. So what am I missing?

Yeah. So our ancestors viewed plants with a lot of suspicion. And whenever they had a chance, they would take them out of their diet. They ate plants out of necessity because there was nothing else. They ended up, our ancestors ended up hunting out all the big mammals. And so what they ended up with were plants. And then they became really good at detoxifying those plants and processing them so that they minimize the harmful effects

because plants have all sorts of clever chemical defenses to deter animals from eating them. And so humans figured out that by doing things like steaming, grating, chopping, boiling, and so on, you could reduce all these harmful effects and you could end up with a pretty good meal at the end of the day. So traditional societies figured out all these kinds kinds of diets and they tasted pretty good. But this is a compromise that our ancestors faced. And what they preferred to eat

was a lot of meat, which is easy to digest and doesn't have this problem of the toxins. So eating plant food then makes sense if you're following a traditional diet. And I don't have any objection to eating plants.

But they're really not a superfood. The research has never supported the effects of plants in promoting long lifespan in a robust way. So let's make a comparison with alcohol. There's much more suspicion about the effect of alcohol, but the research has been much more robust in showing that alcohol promotes long lifespan and reduces heart disease. But that kind of effect has never been as strongly shown with plant foods. And that makes sense because plant foods are really trying to poison us.

They're trying to prevent us from eating them. So I hope that unwells the contradiction. Yeah, it starts to anyway. I'm going to dwell on it for one more moment. I just want to clarify. You're acknowledging that plants are chock full of phytonutrients and antioxidants and all the rest. You're just pointing out that the science hasn't gone further than that to show that all those nutrients are doing us,

like unequivocally show us that those nutrients are getting to the right places in our body and doing wonderful things for us. That's right. And some people take those plant foods to the extreme. Dr. That's right. And some people take those plant foods to an extreme. And so in the case, in the book I talk about a person who, an Indian scientist who took bitter gourd, which is this vegetable that's reputed to reduce the risk of diabetes. And then this doctor turned into a drink. And he and his wife consumed it for four years, and eventually he died, just from consuming too much of this vegetable, because it has this toxin which makes it bitter. And so when most people eat bitter gourd, they can only eat a small amount of it because

it's so bitter. But this doctor, sorry, this scientist, thought he believed in the health benefits of it, and so he deliberately drank all this bitter juice, and then he ended up dying. His wife also suffered severe injuries from drinking this kind of juice. I also give the example in the book of a farmer in France who ate several apples a day, and when he eventually suffered a heart attack, when they autopsied him, they found out that there were all these crystals from the apple peel that were inside his lungs.

And so it's unclear whether he died from eating too many apples specifically, but for sure there was evidence of all these apples that he had eaten over his lifetime. And a third example would be Steve Jobs. He went through these periodic food fasts, and he ended up dying from pancreatic cancer. And it's unclear whether that pancreatic cancer was specifically related to his diet, but an actor who tried to play Steve Jobs

went on a food diet and ended up in the hospital also with pancreatic issues from eating only fruits for a month. So there's nothing wrong with eating fruits. There's nothing wrong with eating apples or bitter gourd in moderation. But humans are great at taking things to the extreme, and that's in the danger, I think, as well. Steven, as we close out our conversation, I wanted to try and ask you to apply your thoughts and your main ideas in this book to the modern challenge of trying to figure out the right diet. And, and so I thought

I would ask you to comment on a few different popular, uh, food philosophies, I suppose. Um, so, so I think, I think I'll start with one that you actually address in your book and I'll just ask you like what, just to give me your, your own take on, on the paleo diet and and whether it's good or bad or somewhere in between the paleo diet um is effective in in some ways it's effective in increasing people's good mood and this this is plausible because um paleo diet, people end up eating a lot of animal foods and they have increased levels of cholesterol. And cholesterol is a precursor for sex hormones. And so people who end up eating the paleo diet say that they have improved sex drive.

And they have this overall feeling of well-being. drive and they have this overall feeling of well-being. So I think if that's a goal, the paleo diet will help achieve that. The possible drawback of the paleo diet is that eating a lot of bread and processed meat could shorten a person's lifespan. So some people are willing to make this kind of trade-off. They're willing to shave a couple of years off their life if they're going to end up with a better well-being in the short term. And people who also change to a paleo diet may end up losing weight at least for a couple of years.

The problem with the paleo diet is that besides the problem of a shortened lifespan, it's also really hard to maintain psychologically because people are cutting out a lot of food that they really enjoy eating. Things like bread and pasta and potatoes. So it's difficult

psychologically. It could shorten a person's lifespan, but it could also improve a person's mood in the short term and help them lose weight in the short term. So I think as long as people are aware of these consequences, then yeah, everyone's free to make their choices. Okay, so this is the last one. And you probably know this one because a lot of people do. of people do, but it's Michael Pollan's food philosophy or axiom that he's been repeating, which is eat food, not too much, mostly plants. What do you think about that axiom?

So first of all, this kind of philosophy is not going to make sense for people who live in the north, let's say the Inuit or the Maasai, who historically have eaten a lot of blood and milk and meat. So I think there are some populations in the world where they're just going to eat less plant foods, and it's going to be fine for them. But Michael Pollan himself acknowledges that this kind of his philosophy is aimed at, let's say, the mainstream America. And so I think in that case, it's simple, it's easy to remember, and we'll end up increasing a person's lifespan, most likely.

The problem is then that another potential problem is that some people have a particular gene that will make them acquire more weight when they eat starches. And so people who have this genetic gene, they will end up increasing weight when they eat a lot of plants compared to a diet that has a lot of meat. And so for those people, they're not going to be too happy about this kind of philosophy. So I think Michael Pollan's philosophy, it sort of applies to a wide range of people in the United States, but specific people who have the genetic tendency to acquire more weight from eating starches, they may want to stay away, actually, from eating plant foods.

So it makes sense for them. So I think we have to fine-tune this kind of advice for particular kinds of people. All right, Stephen. Well, last question then. Let's end with your food philosophy as applied to me, and that's because I think I represent a type of person who, well, I don't have a very specific ancestry that I know of. And I know I have to know, I have to assume you've been asked this question a million times now. Um,

but, but what, what does someone who doesn't have a specific ancestry do? What is, what does their food philosophy need to be? What would you suggest to them? Um, so I would have two lines, two easy-to-remember sentences. The first would be, think cuisine, not nutrition. And the second would be to keep moving.

So the first line, think cuisine, not nutrition. I think someone like yourself, you can't change the attitude to a specific region of the world. That means you have a lot of culinary options. There's a lot of traditional cuisines that are available and are great to eat.

You can have your pick of Japanese, Thai, Mediterranean, Scandinavian, or Native American, Native Australian, whatever. So there's a lot of different foods to eat around the world that are going to taste great and they're going to maintain your health and they're also going to be great for the environment. So I think you have really a lot of options. But underlying that would be the idea of being physically active throughout the day. So if you can do that, then you can really enjoy your food. Well, Stephen Lay, I really enjoyed your book

and I've really enjoyed this conversation. And so I just want to thank you very much for joining me on the podcast. Okay, thanks for chatting with me. All right. So that's it, folks. I hope you enjoyed that. Don't forget to go and check out a copy

of 100 Million Years of Food if you liked what you heard in that interview. It's a pretty fascinating book, a lot more detail than we covered. And yeah, it's available everywhere. On that note, as I said, if you are a Canadian listener and you would like to enter a draw for a free copy of the book to be sent to you by the Canadian publisher of the book, then either share

the post for this episode from the ruminants Facebook page on your own timeline or retweet this episode's tweet. Go and find that at ruminant blog on Twitter or send me an email and just tell me some thoughts you have about the show. I'll choose a winner and announce it probably next week and I'll talk to you next week. Have a good one. Because why would we live in a place that don't want us A place that is trying to bleed us dry. We could be happy with life in the country, with salt on our skin and the dirt on our hands. I've been doing a lot of thinking, some real soul searching, and here's my final resolve. I don't need a big old house or some fancy car to keep my love going strong.

So we'll run right out into the wilds and braces. Ride out into the wilds and graces We'll keep close quarters with gentle faces And live next door to the birds and the bees And live life like it was meant to be Bye.